The pollen that fertilizes the stigma may come from the same flower or from a nearby flower. Many flowers are fertilized (or pollinated) by insects. The flowers produce drops of sweet liquid called nectar at the base of their petals. When insects visit the flower to drink the nectar, pollen from the anthers rubs off onto their wings, bodies and legs. When the insect visits another flower, the pollen is deposited on its sticky stigma.
Fertilization is a process of sexual reproduction in plants, which occurs after pollination and germination. Fertilization can be defined as the fusion of the male gametes (pollen) with the female gametes (ovum) to form a diploid zygote. It is a physicochemical process which occurs after the pollination of the carpel. The complete series of this process takes place in the zygote to develop into a seed.
In the fertilization process, flowers play a significant role as they are the reproductive structures of angiosperms (flowering plants). The method of fertilization in plants occurs when gametes in haploid conditions fuse to produce a diploid zygote. In the course of fertilization, male gametes get transferred into the female reproductive organs through pollinators (honey bees, birds, bats, butterflies, flower beetles) and the final product will be the formation of the embryo in a seed.
In flowers, the pollen grain germinates after the pollination of the carpel and grows into the style by creating the pathway for the pollen grain to move down to the ovary. The pollen tube breaks into the ovule through the micropyle and bursts into the embryo sac. Here the male nucleus fuses with the nucleus of an egg inside the ovule forming a diploid zygote, which later swells up and develops into a fruit.
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